A frequency reusing method in a wireless communication system including a coverage region, which has first, second and third regions, and a radio access station (RAS) transmitting a traffic to a portable subscriber station (PSS) in the coverage region, comprises (a) transmitting the traffics by assigning an identical frequency band to the first, second and third regions during a first interval; (b) transmitting the traffics by assigning the identical frequency band to the first region during a second interval; (c) transmitting the traffics by assigning the identical frequency band to the second region during a third interval; and (d) transmitting the traffics by assigning the identical frequency band to the third region during a fourth interval.